Pad Touch Move

padTouchMove.js

document.getElementById('someid').addEventListener('touchmove', function(event){
	var centroid = { x: 0, y: 0 };
	for(var i=0; i<event.targetTouches.length; ++i) {
		centroid.x += event.targetTouches[i].pageX;
		centroid.y += event.targetTouches[i].pageY;
	}
	centroid.x /= event.targetTouches.length;
	centroid.y /= event.targetTouches.length;

	document.getElementById('messageBox').innerHTML = 'touch centroid: ' + centroid.x + ',' + centroid.y;
	event.preventDefault();
}, false);